As a cell analyzer for analyzing cells contained in a biological sample collected from a living body, a cell analyzer for measuring epithelial cells of the uterine cervix contained a sample collected from the uterine cervix of a subject by a flow cytometer and screening cancer and atypical cells is conventionally known (e.g. European Patent publication No. EP2261632).
In addition to the epithelial cells to be analyzed, contaminants such as red blood cells and white blood cells are also contained in the sample collected from the uterine cervix of the subject. When such a sample is measured as it is, the presence of the contaminants affects the measured results, resulting in being unable to perform an accurate screening. Therefore, it is necessary to discriminate the epithelial cells to be analyzed from the contaminants.
In the apparatus described in European Patent publication No. EP2261632, the epithelial cells are discriminated from the contaminants by trapping the epithelial cells to be analyzed in a filter, aspirating the contaminants passed the filter, and discharging them using the fact that the size of the epithelial cells to be analyzed is larger than that of the contaminants.
In order to prepare a measurement sample containing the epithelial cells, it is necessary to detach the epithelial cells trapped in the filter from the filter and recover them. The detachment is performed by applying a shearing force generated by rotating a rotor arranged adjacent to the filtration surface of the filter to the surface of the filter.
In the cell analyzer described in European Patent publication No. EP2261632, when detaching the epithelial cells attached to the filter by the rotor, the rotor may not rotate or the rotation may not be sufficient due to reasons that the epithelial cells are adhered to the rotor or the wall surface around the rotor. When the rotation of the rotor is not sufficient, the epithelial cells to be measured cannot be sufficiently taken.